<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Title</title>
</head>
<body>
<div>aaa</div>
<div class="header">bbb</div>
<div id="ab">ccc</div>

<script>
function Person() {
    this.name = 'aa',
	this.age=18;
}
Person.prototype.length = 100;
Person.prototype.width =500;

var p1 = new Person()

/*Object.keys(p1).forEach((value,index)=>{
	console.log(value,index)
})*/

for(let key in p1){
	console.log('for in:',key);
	if(p1.hasOwnProperty(key)){
		console.info('独有的',key)
	}
}
</script>
</body>
</html>